I've heard more than one anti-Grant person say that the reason Grant was so successful in his Civil War military career was because he was so lucky. I'm not buying all of that, of course, but I think there is some merit in it. There had to be some luck involved in crossing both the Mississippi and the James rivers without any significant — if any — losses. You could also argue that he was unlucky, just missing getting to Spotsylvania before Lee, or even Cold Harbor, where if he didn't have to wait a day for Hancock to get into position, he might have been abel to attack a then-untrenched Lee a day earlier. The pendulum of luck swings both ways.